I have a healthy litter of 8 medium/large breed puppies.  I started their second course of worming at 5 weeks yesterday and one is particularly sleepy today.  He is by no means the smallest, but he is the fluffiest and it has been a very hot day today.
Should I continue the full worming course, or stop and look to restart in another week?

We wormed out litters with Sherleys Gentle Worming Syrup, at 2 weeks, and then every 2 weeks to the time they went home - with their new owners given full details, dates given and with what, and advice to re worm at 3 months.

It is hot today so it could just be that.

I haven't heard of worming causing sleepiness/drowsiness - that's not a known side effect.  I'd assume it is the heat and would continue with the worming.

PS You can give them something cool to lie on, like large floor tiles/stones....

Is this a breed that could carry MDR1?

Thank you. It seems it could have been a combination of both. Hiccups today in him as well but much perkier tonight, in the cool and with lots of air about